# builtins with exit status inverted
( true )
echo $?
( ! true )
echo $?
( false )
echo $?
( ! false )
echo $?
# inverting shouldn't affect exit
(exit 42)
echo $?
( ! exit 42 )
echo $?
# commands requiring an exec with exit status inverted -- broken in bash-2.04
( ls > /dev/null 2>&1 )
echo $?
( ! ls > /dev/null 2>&1 )
echo $?
touch /tmp/notwrite
chmod 400 /tmp/notwrite
# make sure redirection failures in commands whose exit status is inverted
# are handled correctly
( ls > /tmp/notwrite ) 2>/dev/null
echo $?
( ! ls > /tmp/notwrite ) 2>/dev/null
echo $?
# now add exit traps, true and false for commands with and without exit
# status inversion
(trap 'false' 0 ; ! ls > /tmp/notwrite ) 2>/dev/null
echo $?
(trap 'false' 0 ; ls > /tmp/notwrite ) 2>/dev/null
echo $?
(trap 'true' 0 ; ! ls > /tmp/notwrite ) 2>/dev/null
echo $?
(trap 'true' 0 ; ls > /tmp/notwrite ) 2>/dev/null
echo $?
rm -f /tmp/notwrite